Home Forums General Discussion Technical Questions OTIS 6850 crash stopping between floors

Hi People
Late 1950's Otis 6850 selector and controller ( 6164 relays ) Duplex pair of gen set lifts, 1 lift crash stopping between floors, both up and down. the main lift is running AOK
Will drive off XU or XD but will crash stop imediately instead of going to the next floor when the relay is released, and will respond to a landing call to a floor but will crash stop about 3 feet short every time.
levelling ring , is also obviously between between ramps/ LV cams, and all contacts are clear of the LV ramps in travel.
Wish I was a good enough engineer to get through this one which is probably very basic.
Also in the same mode... can any one send me a very basic relay operating sequence so that I know what is supposed to be occuring when all is well with this type of controller
Any help would be appreciated
many thanks
Agtrak100

Watch the controller next to it, observe what relays come in, (or drop out), and when they do so in the stopping sequence.

Does this selector have an advancer panel? What is happening with the dogs and pawls when it "crashes" to a stop? Is it actually dogging out, or are the dogs just dragging the pawls?

I'll see if I can find my operating sequence, but honestly, I haven't used it in 20 years....

Hi Vic
many thanks for the reply..
The motor room is a bit of a mess... layout wise and it is a bit of bugger to get at the other panel so that you can observe what is going on the over speed govener is right in front of it and then the selector is right up against that!!!!!!
The selector does not have an advancer panel.
It would be brillaint if you could manage to find your "old " operating sequence.

Nice car by the way is it yours... no way we can afford to run those over here petrol is �7.00 per gallon!!!!!!!!! or in your money $11.00 per gallon...

Many thanks
Agtrak100

Its been many years since ive looked at one of these. What controller is it 10, 20, 30 UCL.? Check the contacts on your cross head panel opposite of the floor bars. Look over the traveling cables that follow the ring and panel. When the car starts its run does the ring lift? Is the ring still up when the car stops?

is this happening in the same spot every time? i would hold a meter on the lv contacts and your pawl mag coil and wiggle your selector t-cable see is your dropping voltage.

hi ag. it certainly sounds like you have a contact fault with the slow down cct. its always alot easier to sequence relays with another lift next to you. if you notice ux/dx not coming in and on the other controller it does, find when the timing tells you it should be in, then just try pushing in the relay at that time and see if the lift levels in.if it does it certainly looks like you have a brush or contact fault whether its those or a trailing wire fault. either way you need to get the sequence right and alot of times over here the tuners used to write in pencil on the side of the selector the divisions from the master floor.

Hi People
many thanks for the info... All sorted
LV contacts on the Levelling carriage not making and also dirty contacts on the ladder I think they are called hook switches.
If you punch the lift up or down using XU or XD, it will mask this problem as you are effectively bridging out the hook switches...
All down to poor maintenance ... an hour visit time for a controller like this is NOT enough.. what part of this do people like been counters not understand about this.
There are 8 of these lifts on site and all bar one are GREAT machines, now I have even got the homing and Duplexing to work correctly on this lift pair. Great.. all good

All the best and many thanks
Agtrak100

Great show, mate.

If I find the sequence of operation tutorial, I will create a PDF file, and email it to you. It will take me a few days to look around.

Cheers!

Hi Vic
many thanks for your reply.
the operating sequence would be a very big help if you do manage to find it.. alot goes on in these controllers and quickly ....

All the best, from would you believe it a drought ridden England.

Agtrak100